Micah Sweet
Level Up & OSR Enthusiast
If you prefer ascending AC, and your players are on board, I suggest just do it. It would take relatively little work to adjust. Several OSR designers have in fact done it for you I suspect.
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D&D 1E AD&D players and referees, what do you think of ascending AC?
- Thread starter overgeeked
- Start date
Oh ok. Because I've had those arguments, and it really comes down to "I like chocolate ice cream" vs. "You like strawberry ice cream". No amount of logic, reason, or explanation will get anyone to admit that any change to the game since WotC took over has been anything but the Devil's work, but ascending AC is the one that always gets brought up (either that or unified xp for all classes).
I mean, I got a host of grievances with WotC personally, but this always struck me as a strange hill to plant one's flag on.
Flynn Flanagan
Villager
Works fine either way for me.
overgeeked
B/X Known World
I mean, it's all the same math it just depends on when you want to do it and how often. Anything that saves time, I'm for. So ascending AC makes more sense. But I know a fair few AD&D grognards who would die on that hill, so wanted to take the temperature somewhere.
The Sigil
Mr. 3000 (Words per post)
The problem as I see it is that even in AD&D we abstracted sufficiently and use terminology that obfuscates what we're trying to communicate.
We see things like "Armor Class 5" or "Armor Class -2" and what we've abstracted away is the notion that "Magic Plate and Shield is First Class Armor" (i.e., AC 1), and things after that are "Second Class" or "Third Class" (or "Lesser Class").
The fact that Armor Class can go into negative numbers means we overthought the system. Now it's just a mathematical construct instead of what it was originally intended to do...
"Best Armor" = First Class (AC 1)
"Really Good Armor" = Second Class (AC 2)
"Good Armor" = Third Class (AC 3)
... and so on.
Since we're no longer using AC 1 as shorthand for "the best armor" it now becomes the question of which is the easier mathematical operation:
ASCENDING AC: Start with a hit roll. Sum all the bonuses that may apply due to magic, high ability scores, Proficiency/Base Attack/Bonus etc. Compare this final value with the armor class of the defender. If the final result is greater than or equal to the AC of the defender, the attack hits.
DESCENDING AC: Start with a hit roll. Sum all the bonuses that may apply due to magic, high ability score, etc. Subtract this modified roll from your THAC0 score. Compare this final value with the armor class of the defender. If the final result is less than or equal to the Armor Class of the defender, the attack hits.
ALTERNATIVE DESCENDING AC: Start with a hit roll. Sum all the bonuses that may apply due to magic, high ability score, etc. Subtract your defender's AC from your THAC0 score. If your modified hit roll is greater than or equal to the result of subtracting the defender's AC from your THAC0 score, you hit.
One of these has a lot more steps, including at least one subtraction step (and whether or not we want to admit it, the average person finds addition easier than subtraction, also the "less than" function is confusing when comparing two negative numbers). I think using Ascending AC is a lot cleaner. To say nothing of the counterintuitiveness of magic armor and shields in the Descending AC paradigm LOWERING your armor class by the amount of their "plus" (e.g., "take a fighter in plate mail with a shield... he has an AC of 2. Now hand him a +3 shield. His AC is now -1. Yup, 2 plus 3 equals minus 1.")
(I grew up with THAC0 and have no problem immediately looking at a hit roll, a THAC0, the target AC, and knowing whether or not the attack is a hit. Just because I learned it doesn't mean the math is intuitive... just because I can do multi-dimensional linear algebraic transformations and after years of practice they're somewhat intuitive to me does not make them intuitive to most)
We see things like "Armor Class 5" or "Armor Class -2" and what we've abstracted away is the notion that "Magic Plate and Shield is First Class Armor" (i.e., AC 1), and things after that are "Second Class" or "Third Class" (or "Lesser Class").
The fact that Armor Class can go into negative numbers means we overthought the system. Now it's just a mathematical construct instead of what it was originally intended to do...
"Best Armor" = First Class (AC 1)
"Really Good Armor" = Second Class (AC 2)
"Good Armor" = Third Class (AC 3)
... and so on.
Since we're no longer using AC 1 as shorthand for "the best armor" it now becomes the question of which is the easier mathematical operation:
ASCENDING AC: Start with a hit roll. Sum all the bonuses that may apply due to magic, high ability scores, Proficiency/Base Attack/Bonus etc. Compare this final value with the armor class of the defender. If the final result is greater than or equal to the AC of the defender, the attack hits.
DESCENDING AC: Start with a hit roll. Sum all the bonuses that may apply due to magic, high ability score, etc. Subtract this modified roll from your THAC0 score. Compare this final value with the armor class of the defender. If the final result is less than or equal to the Armor Class of the defender, the attack hits.
ALTERNATIVE DESCENDING AC: Start with a hit roll. Sum all the bonuses that may apply due to magic, high ability score, etc. Subtract your defender's AC from your THAC0 score. If your modified hit roll is greater than or equal to the result of subtracting the defender's AC from your THAC0 score, you hit.
One of these has a lot more steps, including at least one subtraction step (and whether or not we want to admit it, the average person finds addition easier than subtraction, also the "less than" function is confusing when comparing two negative numbers). I think using Ascending AC is a lot cleaner. To say nothing of the counterintuitiveness of magic armor and shields in the Descending AC paradigm LOWERING your armor class by the amount of their "plus" (e.g., "take a fighter in plate mail with a shield... he has an AC of 2. Now hand him a +3 shield. His AC is now -1. Yup, 2 plus 3 equals minus 1.")
(I grew up with THAC0 and have no problem immediately looking at a hit roll, a THAC0, the target AC, and knowing whether or not the attack is a hit. Just because I learned it doesn't mean the math is intuitive... just because I can do multi-dimensional linear algebraic transformations and after years of practice they're somewhat intuitive to me does not make them intuitive to most)
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overgeeked
B/X Known World
Extra math and extra chart look ups add time and make things slower. Removing math and chart look ups speeds things up.
If you've been doing it so long you have the thing memorized, that's an extreme edge case which will not be true for the vast majority of people.
The mystery should be in the fiction, not the rules.
It's even faster if you skip the combat matrix entirely.
Just like the combat matrix.
And the number the player rolls being the TN of hitting the monster removes that extra, unnecessary step.
Micah Sweet
Level Up & OSR Enthusiast
To be fair, your general preference is for practically no rules at all though, right? Aren't you a fan of FKR? No surprise you're pushing hard for simplicity here.
overgeeked
B/X Known World
Exactly. The math is identical either way, it's more about when and where you do that math.
In ascending AC, you have to compare a reported number with a number on the monster's stat block, which takes less time than taking the player's reported number and either looking it up on a chart and cross referencing that with a number from the monster's stat block (combat matrix), or doing extra math to it (THAC0), to figure out the same info.
deganawida
Legend
Let us know how it goes! I’ve never played first edition, but lately, after yielding to my daughters’ desire to run 5e for them, I’ve been considering learning the system and running for my normal group.
overgeeked
B/X Known World
I've played and run AD&D since about 1984, but never with ascending AC. It all depends on what the players think of the change and if they'll accept it.
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